<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<link rel="stylesheet" type="text/css" href="task.css">
	<script type="text/javascript" src="message.js"></script>
	<script type="text/javascript" src="validate.js"></script>
</head>
<body>
	<div id="form">
		<div class="item">
			<span>名称</span>
			<input type="text" name="">
			<button>验证</button>
			<div class="about">必填，长度为4~16个字符</div>
		</div>
		<div class="item">
			<span>名称</span>
			<input type="text" class="" name="">
			<button>验证</button>
			<div class="about">error</div>
		</div>
		<div class="item">
			<span>名称</span>
			<input type="text" name="">
			<button>验证</button>
			<div class="about"></div>
		</div>
	</div id="form">
	<script type="text/javascript" src="task.js"></script>
</body>
</html>